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14 DESIGN007 MAGAZINE I JUNE 2019 imperial for dimensions and vice versa, and the format is frequently different from that of the image data. Presumably, if you have a spe- cific format for the image data, the NC drill file should have the same numeric tolerance, so mixing numeric data formats should be avoid- ed. The most typical NC drill format is set to "inch" for both the tool size and the dimen- sions. The most used formats are 2:4 (for posi- tional accuracy) and trailing zero suppression. Now that I have gotten off my soapbox, let me end by saying that a good CAM operator can always figure out the proper numerical format to match the NC drill drawing. But do yourself a favor by at least making them con- sistent. Don't make the non-plated tool file one format and the plated holes another. Likewise, do not make the blind vias, buried vias, and through-holes all different numerical formats. As Rick often says, "Don't take things for granted and don't believe everything you read until you have proved them for yourself empir- ically or by making mistakes." Thanks again, and as always, feel free to contact me any time. DESIGN007 Mark Thompson is in engineering support at Prototron Circuits. To read past columns or contact Thompson, click here. Thompson is also the author of The Printed Circuit Designer's Guide to… Producing the Perfect Data Package. Visit to download this book and other free, educational titles. Collaborating scientists at the U.S. Department of En- ergy's Ames Laboratory, Brookhaven National Laboratory, and Princeton University have discovered a new layered ferromagnetic semiconductor, a rare type of material that holds great promise for next-generation electronic tech- nologies. The researchers discovered ferromagnetism in a vanadium-iodine semiconductor, a material which has long been known but ignored. "Being able to exfoliate these materials down into 2D layers gives us new opportunities to find unusual prop- erties that are potentially useful to electronic technolo- gy advances," said Tai Kong, a postdoctoral researcher in the lab of Robert J. Cava, the Russell Wellman Moore Professor of Chemistry at Princeton University. "It's sort of like getting a new shape of Lego bricks. The more unique pieces you have, the cooler the stuff you can build." The advantage of ferromagnetism in a semiconduc- tor is that electronic properties become spin-dependent. Electrons align their spins along internal magnetization. "This creates an additional control knob to manipulate currents flowing through a semiconductor by manipulat- ing magnetization, either by changing the magnetic field or by other more complex means, while the amount of current that can be carried may be controlled by doping (adding small amount of other materials)," said Ames Lab- oratory Scientist Ruslan Prozorov. "These additional ways to control behavior and the potential to dis- cover novel effects are the reason for such high interest in finding in- sulators and semiconductors that are also ferromagnets." (Source: Princeton University) Researchers Identify New 2D Insulators With Ferromagnetic Properties

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